CROCODILES. 345 



part from the palatal sinus being wanting ;' in this the front 

 of the lower jaw consisting of the left dental from the 1st to 

 the 8th tooth, and of the right from the 1st to the 4th, is 

 fixed— the fragments of the upper and lower jaw being- 

 united : a point proving that some at least of these remains 

 were inhumed before the disintegration of the muscles and 

 integument connecting them ; and, secondly, the posterior 

 part of the skull, from the occipital to the front of the orbits, 

 of an adult, but of a smaller animal than the preceding. 



The 4th tooth in each side of the lower jaw being received 

 into a groove into the upper, the form and size of the cranial 

 foramina, together with those of the protuberances and in- 

 dentations of the muzzle, place our fossil amongst the true 

 Crocodiles, the species being allied to Cuvier's Biporcatws, or 

 the Crocodile, ' a deux arretes' now existing in these rivers. 



The following measurements will facilitate the reference to 

 Cuvier's ' Ossemens Fossiles,' and be perhaps of still further 

 use in providing the means for general reference on points 

 relating to the existing Crocodile (See p. 346). 



From the sutures being obliterated on the upper rugged 

 surface of the fossil, the junction of the lachrymal and 

 anterior frontal on the maxillary bone is not observable, and 

 as this is one of the points upon which the Cayman and Croco- 

 dile differ, it is perhaps to be regretted that this must remain 

 at present doubtftd ; for although the characters above given 

 distinguish the fossil from the Cayman, the bluntness of the 

 muzzle and the proportions of the bones of the head do, in 

 some respects, assimilate it with the latter sub- genus. 



On the lower smooth surface the sutures are well defined, 

 and it is on this measurement that we observe the remark- 

 able distinction between the existing and the fossil animal ; 

 the shortness of the maxillary bones and the length of the 

 intermaxillaries, including the nasal aperture, are peculiarities 

 that will be observed in the table of measurements, the 

 former (maxillary) in the existing animal being to the latter 

 (intermaxillary) as 3-9 is to 3*2 ; in the fossil as 3-8 is to 

 4*3. The length of the maxillary bones on the lower suture, 

 or the space separating the palatine from the intermaxillaries, 

 is rather greater in the existing animal of 11 feet than in 

 the fossil. The comparative measurement from the point of 

 the muzzle to the maxillary extremity of the palatine bone, 

 together with those across the skull at the 10th and 4th 

 teeth, will point out in a still clearer way the bluntness and 

 breadth of the muzzle of the fossil animal. By the extension 

 of the intermaxillaries and the great length of the connecting 

 suture between the point of the muzzle and the nasal aper- 



' Brit. Mus, No. 39,801.— [Ed.] 



